Deck/Pergola Design

Franklin · Aug 05, 2014 2:51 pm

I am planning a deck/pergola for the NW corner of my double brick house. It is my first DIY project. Hoping some people are able to share some wisdom with me on a few confusing points.
1. Is this correct- If its under 25sqm it is exempt development. It'll probably be closer to 30sqm, but would you make it a bit smaller just to avoid having to deal with council? or is that crazy talk? I am meant to get a copy of the aus building codes for jobs like this?
2. Under deck ventilation/drainage/grass. Thinking the deck will be approx. 30cm off the ground. What do you do about ventilation/access to check for termites? It seems to small to climb under and have a look? Is there enough ventilation just in the slats between the boards? Can I put garden beds/steps all around the facing of the deck ( I mean between the top of the deck and the ground at its front), or will that inhibit air flow too much? We live on a soggy block and have had some issues with mold/sogginess under the house. Do I just cover the grass with plastic and gravel?
3. I am reluctant to mess around with attaching anything to the double brick. Will it work to run bearers parallel to the house ( not touching), so essentially its a free standing deck? The pergola will attach at the top though.
4. Has anyone used the recycled plastic decking boards? Any good?

Thankyou kindly

Stewie D · Aug 06, 2014 12:02 pm

Quote:

1. Is this correct- If its under 25sqm it is exempt development. It'll probably be closer to 30sqm, but would you make it a bit smaller just to avoid having to deal with council? or is that crazy talk? I am meant to get a copy of the aus building codes for jobs like this?

Correct, although that will depend on your council too however as soon as you mention a roofed structure you will have to apply for a DA. Personally I'd make it the right size and go through the council even though it will cost more.

Quote:

2. Under deck ventilation/drainage/grass. Thinking the deck will be approx. 30cm off the ground. What do you do about ventilation/access to check for termites? It seems to small to climb under and have a look? Is there enough ventilation just in the slats between the boards? Can I put garden beds/steps all around the facing of the deck ( I mean between the top of the deck and the ground at its front), or will that inhibit air flow too much? We live on a soggy block and have had some issues with mold/sogginess under the house. Do I just cover the grass with plastic and gravel?

Get your site drainage in order first otherwise you will compound the problem by restricting access to that side of the house. You can always have the first five or six boards screwed down for access to visually inspect the house wall under the deck.

Quote:

3. I am reluctant to mess around with attaching anything to the double brick. Will it work to run bearers parallel to the house ( not touching), so essentially its a free standing deck? The pergola will attach at the top though.

Why? A simple sleeper plate bolted to the house wall is a standard way of fixing decking frames to a house.

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4. Has anyone used the recycled plastic decking boards? Any good?

Some of it is quite good and maintenance free however it can still fade a bit and look a bit "plasticky".

Stewie

Franklin · Aug 07, 2014 6:26 am

Stewie, thanks so much, some great info there. With the drainage situation, might it work better if instead of a deck, it was a concrete slab patio (the deck was never gonna be high) below the vent holes in the brick and slightly sloped away from the house? Better or much of a muchness? Cheers

Stewie D · Aug 07, 2014 9:17 am

Probably much of a muchness as long as you don't compromise the efficiency of the existing vents.
It is up to you as to what you want. A timber deck or a tiled patio. Both have their pros and cons,

Stewie

ppp4411 · Aug 31, 2014 11:18 pm

Just wondering how much cost saving for DIY vs trades ? if you only spend weekend for this DIY job, how long do you think it takes?

Knowing I have not much of reno experience, I am juggling between both.

Leonardo_23 · Sep 22, 2014 1:26 am

Hi ppp4411,

Firstly is there to be a roof. A roof makes the pergola a verandah and different rules apply especially if you load the existing house lintels or overhanging rafters via the fascia.

What state, what country etc. also matters as Stewie said.

In Vic, the clearance under a house floor frame needs to be 400mm under bearers in a termite risk area unless the deck is no wider than 2 metres I think, but you should ask your local building surveyor about this, because that 2 meter rule is for under houses and decks are not mentioned.

About savings by being an owner builder, permits aside, 40% of the job is labour approximately.

Leonardo_23

Saint Mike · Sep 22, 2014 8:23 am

Re the "plastic wood". It can look good and last. If you pick a quality one.

If you use real wood you'll need to keep it well and look after it. Not sure where you are - but climate might also affect the decision. Do you get sea winds (ie salt), high humidity, lots of rain, long dry spells etc.

I wouldn't dismiss the "plastic wood". Extrapolated over - say - 10-15 years - it might be a better and cheaper option. Especially if termites are a worry.